Copper Alloy CC481K-GM (Permanent (chill) mould cast)
Finish state
EN CC481K
Choose for medium-to-large series of small bushings and worm wheels where a finer, denser structure and tighter tolerances are needed.
Values for the GM condition
Other CC481K tempers and conditions
CC481K is listed in 4 conditions; see the grade overview at CC481K.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Sand cast | Choose for one-off or large, complex bearing housings, worm wheel rims and pump parts where section thickness varies. | 190 | 310 | 6 | 95 HB | 11 % IACS |
GMThis page Permanent (chill) mould cast | Choose for medium-to-large series of small bushings and worm wheels where a finer, denser structure and tighter tolerances are needed. | 220 | 350 | 4 | 110 HB | 11 % IACS |
GCDefault Continuously cast bar/tube | Default stock condition: continuously cast round bar, hollow bar and tube for machined bushings, nuts and thrust washers. | 230 | 380 | 8 | 105 HB | 11 % IACS |
Centrifugally cast | Choose for large-diameter, heavily loaded bushings, sleeves and worm-wheel rims needing a dense, porosity-free wall. | 240 | 400 | 8 | 110 HB | 11 % IACS |
What is CC481K-GM?
CC481K-GM is CC481K supplied in the GM condition — choose for medium-to-large series of small bushings and worm wheels where a finer, denser structure and tighter tolerances are needed. CC481K-GM has a yield strength of 220 MPa (31.9 ksi) and a tensile strength of 350 MPa (50.8 ksi) — weaker than 51% of copper alloy grades. Elongation at break is 4% and the elastic modulus is 110 GPa (16 Msi). CC481K-GM has a density of 8.8 g/cm³ (0.318 lb/in³), heavier than 58% of copper alloy grades. It melts at 830°C (1,526 °F). GC is the default condition FabDigit quotes; GM is available on request or by drawing note.
Limitations
- Limited formability — 4/100, worse than 100% of copper alloy grades
- Limited ductility — 4%, worse than 96% of copper alloy grades
- Difficult to weld — 20/100, worse than 88% of copper alloy grades
- High embodied carbon — 4.8 kg CO₂/kg, worse than 84% of copper alloy grades
CC481K-GM properties
Typical room-temperature values for CC481K-GM; 22 are specific to this condition. Other listed values are CC481K reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
CC481K-GM has a density of 8.8 g/cm³ (0.318 lb/in³), heavier than 58% of copper alloy grades. It melts at 830°C (1,526 °F).
Mechanical13
CC481K-GM has a yield strength of 220 MPa (31.9 ksi) and a tensile strength of 350 MPa (50.8 ksi) — weaker than 51% of copper alloy grades. Elongation at break is 4% and the elastic modulus is 110 GPa (16 Msi).
Thermal6
CC481K-GM is rated for continuous service to 250°C (482 °F). It conducts heat at 47 W/m·K (27.2 BTU/hr·ft·°F), worse than 69% of copper alloy grades. Thermal expansion is 18.4 µm/m·K (10.2 µin/in·°F).
Electrical3
CC481K-GM conducts electricity at 11 % IACS, worse than 68% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (66/100), better than 64% of copper alloy grades.
Sustainability4
Producing a kilogram of CC481K-GM takes about 70 MJ of energy and emits 4.8 kg of CO₂ — more than 84% of copper alloy grades. Typical recycled content is 45%.
Manufacturability8
CC481K-GM's machinability is fair (44/100, better than 60% of copper alloy grades); weldability poor (20/100); formability not recommended (4/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with CC481K-GM
Is CC481K easy to machine?
Machines to a fine finish with sharp carbide or HSS tools, positive rake, high speed and light feed; chips are short and abrasive due to δ/Cu₃P — expect ~20–30 % of free-cutting brass throughput and use flood coolant.
Can CC481K be welded?
Poor fusion weldability (hot-shortness, tin oxide); repair only by GTAW with matching phosphor-bronze filler and 150–250 °C preheat, or preferably braze/solder.
Can CC481K be formed, bent or molded?
Cast-only alloy — essentially no cold forming; design generous fillets and directional solidification with chills/risers because of the wide freezing range and micro-shrinkage tendency.
What surface finishes work on CC481K?
Not anodisable; finish by machining/burnishing, polishing, chemical patination, or tin/nickel/silver plating; bearing bores are usually honed or roller-burnished.
CC481K chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Snforms hard δ-phase for wear resistance | 10 – 11.5 | 10.8 |
| Pdeoxidiser; forms Cu₃P hard particles | 0.5 – 1 | 0.7 |
| Pbimpurity limit | ≤ 0.25 | 0.1 |
| Znimpurity limit | ≤ 0.05 | — |
| Niimpurity limit | ≤ 0.1 | — |
| Feimpurity limit | ≤ 0.1 | — |
| Sbimpurity limit | ≤ 0.2 | — |
| Simpurity limit | ≤ 0.05 | — |
| Alimpurity limit | ≤ 0.01 | — |
| Siimpurity limit | ≤ 0.01 | — |
| Mnimpurity limit | ≤ 0.05 | — |
| Curemainder, ~88% | balance | — |
CC481K-GM — frequently asked
What is CC481K-GM used for?
CC481K-GM is typically used for worm wheels, sliding bearings, centrifugally cast bushings and gear blanks. In short: strongest high-tin cast bronze; lead-free bearing bronze; wear-resistant delta-phase casting.
What is the yield strength of CC481K-GM?
CC481K-GM has a typical yield strength of 220 MPa (31.9 ksi) and a tensile strength of 350 MPa (50.8 ksi) — weaker than 51% of copper alloy grades. Strength varies by condition: see the 4 listed tempers.
Is CC481K-GM easy to machine?
Not especially — machinability is rated fair (44/100, better than 60% of copper alloy grades). Machines to a fine finish with sharp carbide or HSS tools, positive rake, high speed and light feed; chips are short and abrasive due to δ/Cu₃P — expect ~20–30 % of free-cutting brass throughput and use flood coolant.
Can CC481K-GM be welded?
Not readily — weldability is rated poor (20/100). Poor fusion weldability (hot-shortness, tin oxide); repair only by GTAW with matching phosphor-bronze filler and 150–250 °C preheat, or preferably braze/solder.
What surface finishes work on CC481K-GM?
Not anodisable; finish by machining/burnishing, polishing, chemical patination, or tin/nickel/silver plating; bearing bores are usually honed or roller-burnished.
Can CC481K-GM be formed, bent or molded?
Cast-only alloy — essentially no cold forming; design generous fillets and directional solidification with chills/risers because of the wide freezing range and micro-shrinkage tendency.
What is the maximum service temperature of CC481K-GM?
CC481K-GM is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between CC481K-GC and CC481K-GS?
GC is the default condition — default stock condition: continuously cast round bar, hollow bar and tube for machined bushings, nuts and thrust washers. GS: choose for one-off or large, complex bearing housings, worm wheel rims and pump parts where section thickness varies. Yield strength is 230 MPa in GC versus 190 MPa in GS.
Sources
- EN 1982 — Copper and copper alloys: ingots and castings (CuSn11P-C / CC481K) — CEN (2017)
- GB/T 1176 — (ZCuSn10P1) — SAC (2013)
- CDA alloy datasheets C90700 / C91100 — Copper Development Association (2023)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol. 13B — Corrosion: Materials — ASM International (2005)
- Continuous-cast bronze bearing bar datasheets (bushing producers) — various (2024)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.